Liouvillian gap and out-of-equilibrium dynamics of a sunburst Kitaev ring: from local to uniform dissipation

Abstract: We consider an open quantum system composed of a $(1+1)$-dimensional Kitaev ring coupled with the environment via $n$ particle-loss dissipators in a \textit{sunburst} geometry. We describe the out-of-equilibrium dynamics of the whole apparatus in terms of Lindblad master equations and focus on the scaling behavior of the Liovillian gap $\Delta_\lambda$ with the system size $L$. We unveil different regimes, which depend primarily on the number of dissipation sources considered in the large-size limit and the dissipation strength $w$, which may be either fixed or attenuated to zero as $w\sim1/L$. In the second part, we develop a dynamic Finite-Size Scaling framework close to Continuous Quantum Transitions to monitor the time evolution of the critical correlations and the entanglement entropy, emphasizing the role of $\Delta_\lambda$ in this regime.